OxygenOffice Professional is a free and open source enhancement of official OpenOffice.org.
OxygenOffice Professional contains more extras like templates, cliparts, samples, fonts and VBA support.
You can use more predefined gradients, colors, and other useful elements, run VBA from Excel documents in Calc, and import Office Open XML (Microsoft Office 2007), Works, WordPerfect files, and T602 documents.
The categories go from Business Correspondence to Presentation and Education.
In each one you can find templates for different type of files, like spreadsheet, presentation, andwriting documents.